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             ___    __    __   _    _             
  ____      / _ \\  \ \\ / // | || | ||   ____    
 |    \\   | / \ ||  \ \/ //  | || | ||  |    \\  
 | [] ||   | \_/ ||   \  //   | \\_/ ||  | [] ||  
 |  __//    \___//     \//     \____//   |  __//  
 |_|`-`     `---`       `       `---`    |_|`-`   
 `-`                                     `-`

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Text this: Green electroluminescence from an n-ZnO: Er/p-Si heterostructured light-emitting diode